Air-vent valve for radiators



L. W. EGGLESTONl AIR VENT VALVE FOR RADIATORS Fled oct. 25, 1921 rlllll Patented July 31, 1928.

UNTED vSTATES PATENT .e orrlca. I

LEWIS W. EGGLESTON, OBUFFALQNEW YORK, ASSIGNOR TO AMERICAN RADIATOR COMPANLOF NEJV YORK, N. Y., A CORPORATION OF NEW JERSEY.

AIR-VENT VALVE FOR RADIATORS.

Application filed October 25, 1921. Serial No. 510,239.

My invention relates to improvements in valves and particularly air vent valves for radiators. It has for one of its objects the provision of a simplified air valve which will readily vent'the air from the heating system without venting steam and wit-hout throwing water; which may be cheaplyv made andthe parts thereof readily assembled.

The invention consists in the improvements to be fully described hereinafter and the novelty ofwhich will be particularly pointed out and distinctly claimed. I have fully and clearly illustrated my invention in the accompanying drawings, to be taken as a part of this specification and wlie1e in:-

Figure 1 is asectional view of an air valve embodying my invention;

Fig, 2 is a sectional view taken on the line Fig.` 3 is a sectional view taken on the line 3-3 of Fig. 1; t

Fig. 4 is a sectional view taken on the lme 4-4 of Fig. 1;

Fig. 5 is an enlargedl detailed section showing the vent opening and the valve therefor; and

Fig.y 6 is a detailed section of a modification of my invention,

Referring to the drawings, in the embodiment illustrated I provide a casing comprising base 1 and a top 2. The b ase 1 at its top is cylindrical in form and is internally screw-threaded as Aat 2a to receive the top. The base, at the bottom of the screwthreaded portion, is provided with an annularseat 3, the purpose of which will more fully hereinafter appear, and below the seat the opposite sides of the base are flattened and drawn in or inclinedtoward each other to form a narrow rounded channel 3a, as shown in Fig. 2. Extending transversely of the base and into the channel 3? is a tubular nipple 4 which snugly ts the rounded portion ot said channel, said nipple being additionally held in position by solder or by brazing, and having its inner open end communicating with the said channel which forms a settling basin for dirt, grit, etc. The outer end of this nipple 4 is screw-threaded at 4b to engage in the threaded tapping 4 in the radiator wall 5 and the inner portion of the nipple at its top is provided with an air inlet opening 6.

Passing through this nipple 4 and extending into the channel 3a is a siphontube 7 which is adapted to project into the radiator as shown in Fig. 1, said tube having its inner end within the body 1, spun or flared outwardly at 7L to prevent its withdrawal from the nipple and at the same time permitting a swiveling and slight longitudinal movement. The nipple 4 at its inner end has a lip or lug 4a formed on its under side which prevents the raising of the Siphon against the top of the nipple and thereby all'ords a clear passage through the nipple above the siphon. The tube 7 serves a purpose, during the normal operation of the valve, to be more :"ully described hereinafter.

The main bodyportion of the top 2 vof the casing is preferably cylindrical in form and at its upper end merges intol a conical portion 2b, which, in turn, at its upper portion mergesinto a more abruptconical portion 10 (see Fig. 5), provided at its central portion with an air vent opening 9 formed by a perforation made through the apex of said conical portion 10. By widely flaring or tapering the casing, as at 10, adjacent the vent opening, the point 11 of the valve 12, to be hereinafter described, will seat on the edge only of the opening 9, thus providing a contact of small'area between the valve and its seat, and preventing the collection of drops of water at this point between the vstem and the adjacent parts of the casing. This arrangement ust described prevents water from being sprayed out of the opening when the valve moves from closed to open position.

For operating the valve I'provide a hollow thermostatic float 13 having a rounded top wall provided with a socket 14 into which the lower end ot the stem 12a of the valve 12 is soldered, and said thermostatic float having an inwardly dished flexible bottom wall 13L preferably having annular concentric corrugations 13b therein. A. guideand stop for the float is provided and comprises apa-ir of arcuate plates 15 connected to each other by a cross piece 16, and having their outer edges clamped between the loweredge of the casing top 2 and the shoulder or seat 3, A yscrew 1.7 extends through an opening in the cross piece 16 to provide an adjustable stop, and fingers 18 upwardly extending, on the plates 15 provide guides for the lloat. Thefout-er edges of the fingers engage the inner walls of the casing and properly center the guide.

Thestructure is suchv that the parts are readily assembled and the valve spaced rela-A tive to its seat at the factory. In assembling the structure the casing top is turned upside down and the float dropped into the top, the valve seating itself due to the shape of the top, the guide is then inserted in the top, and the threaded screw 17 turned up to insure the proper seating of the valve, then given sufficient turn back, preferably about a half turn, to space the valve from its seat to give the correct open position for the valve, after which a drop of solder is placed on the stop to prevent it from working loose. The assembled guide casing and iioat are then placed in position on the base into which has been secured .the nipple 4- with its siphon 7 and the top is screwed down to seat the guide on the shoulder.

.The operation of the valve is as follows Prior to assemblage the hollow float is charged with a suitable volatile which at a 'l predetermined temperature will volatilize to generate sufiicientpressure in the float to outwardly'bow the inwardly dished bottom of the float and thereby raise the float to close the valve.

When the radiator to which the valve is connected is cold the valve will be in position as in Fig. 1 with the vent open. When steam is admitted to the radiator the inflowing steam forces ahead of it the air which has accumulated in the radiator sections and the air passes through the nipple 4 up through the casing between the walls of the float and casing and vout through the vent opening.

As long as cold air only passes through the valve the float will remain down and the inwardly dished bottom contracted thereby leaving the valve open. As soon, however, as the steam following the air strikes the thermostatic float 13 the heat of the steam volatilizes the liquid in the thermostatic float, outwardly bowing the bottom of the fioat which causes the float to rise and closes the valve port 9 against the passage of steam.

It frequently happens that during the escape of air from the radiator the water of condensation in the radiator surges up therein and tends to flow out through the valve. As soon as a slug of water surges into the valve casing the water rising in the casing causes the float to rise closing the vent opening thus preventing the escape of water therethrough, the float remaining up until the water recedes. The water of condensation of a radiator during the admission of steam therein surges bach and forth and upon the rearward or inward surge of the water it will be siphoned out of the valve casing through the siphon tube 7 and at the through the passage in the nipple around the siphon tube and up into the valve. As

the water drains out of the casing the air if permitted to exist forms a seal around thc float and prevents the passage of air above the float thus causing a partial vacuum which prevents the float from dropping to open the valve.

' However, if the area between the walls of the iioatand casing is properly proportioned so that the water will not be held by capillarity to form a seal, the float will drop with the receding of the water from thecasing, promptly opening thevalve to permit the passage of air through the vent opening and the valve will not become water logged. In actual practice in a valve of the size illustrated in the drawings, which are full size, a spacing of one eighth of an inch between the wall ofthe casingand wall of the iioat has given satisfactory results. When the pressure behind the water in `the base drops, the siphon or drain tube 7 will operate-to cause the water to flow out of the base, and at the same vtime airiwill pass into the valve casing through the'nipple and around the tube. This` structure including the tube 7 is particularly"designed for use in the eighth .inch tapping (Briggs standard) which is at present the standard tapping for radiator air valve nipples,`

Another method for accomplishing the same result is to provide a sufficiently large opening in the nipple and into theradiator. If this tapping be increased sufficiently kto accommodate a larger sized nipple the water will escape from the valve and at the same time air will enter the valve. I have found ilo by experiment that a. three-eighths inch tap- It is understood, however, that with. the.

larger sized tapping the spacing between the wall of the'loat and the wall of the casing need not be changed.

It is therefore optional to use the oneeighth inch tapping with a siphon tube as illustrated in Fig. 1 lor to use a three-eighths inch tapping without the siphon as illus-r trated in Fig. 6,as with both vthese structures same time air will pass into the casing I am enabled to obtain satisfactory results. 11H* I have also 'found that the effective area of the vent opening and the weight of the valve and float affect the opening of the valve and should be properly proportioned to. cause the valve to open Linder a predetermined constant pressure, after it has once closed. Due te the fact that there is a differential of pressure between the exterior and interior of the valve casing the weight of the fioat and valve must be suflicient to overcome by gravity the power exerted upon the area. of the valve exposed to the atmosphere through the vent opening. Therefore, in order that the valve will open with air in the casing and at a predetermined boiler pressure, this weight and area should be properly proportioned and the weight tending` to open the valve should be greater than the area of the vent opening times the pressure in the valve casing.

In a structure of the size illustrated I have obtained satisfactory7 results with a pressure in the casing of approximately ten pounds by making the combined weight of the valve and float about six and one half grams.

In order to prevent water from spraying through the vent opening I have provided sufficient spacing above the float to form a separating chamber. In the structure illustrated the distance between the float and top of the casing is approximately one and five sixteenths inches which provides a sufiicient height above the float to permit the water and dirt to drop by gravity before it reaches the vent thus preventing cspraying of the valve.

It will be noted from the above description taken in connection with the drawings, that the thermostatic float member is at all times during the normal operation ofthe valve located in the lower part of the body portion 2, so as to provide an efcient separating chamber above said member, and the valve stem is made relatively slender or ofy small cross-section so as to provide a chamber of considerable volume above said member. By the arrangement just described, in the event the valve casing should contain water insufiicient in quantity to cause the float to close the valve, and air from the radiator should pass up through the water, there will be a sufiicient amount of space above the surface of the water to permit the air to be liberated and pass out of the casing without carrying water with it. -When the conditions in the radiator are such that the water may recede from the valve casing, the water flows from the base of the casing promptly, in view ot the fact that its iiow is not retarded by any capillary attraction within the valve casing, between the fioat and the casing` or elsewhere, and the drain tube 7 assists in and assures prompt flow through the outlet nipple.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. `An air relief valve for radiators comprising a casing having a substantially cylindrical body portion, and a port connecthermostatic float member being spaced from the wall oftl said casinga distance sufficient to preclude holding of water by capillary attraction between said float member and casing wall, and the linterior of the cylindrical and conical portions of the casing above said float member being of suicient height and volume to constitute a separating chamber, and a guide member for said float arranged beneath the float and having spaced guide members extending upwardly between the side Wall of the float and the casing.

2. An-air relief valve for radiators comprising a casing having a substantially cylindrical body portion having an upward tapering conical upper end wall, said end wall having a central vent opening formed by a perforation through the apex of said conical portion, a closed thermostatic float member arranged in the lower portion of said casing and containing a volatile liquid, and a valve stem connected to said float member and provided at its upper end with a valve part formed to make edge contact with the casing wall surounding said vent opening, said conical upper wall being flared widely relative to said point of contact of said valve part toprevent adhesion of water between said wall adjacent said opening and stem, and the interior of said casing being of sufficient capacity above said float member to constitute a separating chamber.

3. An air relief valve for radiators comprising a casing including a vent opening therein, a valve for controlling said vent opening, a closed thermostatic float in said casing and adapted to operate said valve, and a guide for said float comprising a member arranged beneath the float and having upwardly-extending guide fingers extendmg between the outer face of the float and the wall of the casing, said guide fingers cooperating with the outer face of the float.

1.1. An air relief valve for radiatorscom prising a casing including a base and top, the base having a channel in the bottom thereof and a stem fitting said channel and occupying a portion only thereof and having an open end communicating with the rest of the channel, said stem projecting through the base for connecting the valve with a radiator. i

5. An air relief valve for radiators coinprising a casing including a base and top, the base having opposite sides flattened and drawn in toward the bottom to forni a channel, and a hollow stern fitting within said said channel and projecting through the base for connecting the valve with a radi ator.

6. An air relief valve for radiators coniprising a casing including a base and top, said topV having a vent opening therein, a valvel for controlling said opening, a float operating said valve` and a guide for said fioat comprising a pair of arcuate plates clamped between the base and top and having upwardly extending guide lingers.

7. An air relief valve for radiators comprising a casing including a base and a top,

said top having a vent opening therein, a valve, a float operating said valve, and a guide for said float comprising an arcuate plate clamped between the top and base of the casing and having upwardly extending guide lingers fitting within the top. c

8. An air relief valve for radiators comprising a casing including a base and a top, a valve, a float operating said valve, and a stop ineniber for said float having guide fin` gers fitting within the tcp, and having a centrally disposed adjustable stop.

9. An air relief valve for radiators coinprising a casingincluding a base and top, a valve, a iioat operating said valve, and a niernber clampedbetween the top and base of the said casing, said member having upwardlyV extending positioning fingers cooperating with the float, and an adjustable stop.

In witness whereof, I have hereunto subscribed Iny name. Y

Lnwris w. EGGLnsfroNf 

